WASHINGTON (Reuters) - The Food and Drug Administration needs greater authority, more cooperation from other agencies and must do more scientific research to help make the U.S. food supply safer, the General Accountability Office said on Monday.

The FDA also needs to do more to help consumers navigate the maze of food supplements on the market and requires more power to regulate them, the GAO said.

A series of food safety scares has shaken consumer confidence in the food supply, the GAO said. Just last week California-based Caldwell Fresh Foods recalled alfalfa sprouts after salmonella sickened 20 people.

"We found that FDA was hampered in its ability to carry out some food safety responsibilities - oversight of food labels, fresh produce, and dietary supplements - because it lacked certain scientific information," Lisa Shames, director of Natural Resources and Environment for GAO, wrote in a letter accompanying the report.

The GAO, the investigative arm of Congress, said the FDA had tried to meet some of its recommendations but needed to do more.

These needs are becoming more important as the U.S. food supply changes, the report said.

"First, imported food makes up a substantial and growing portion of the U.S. food supply, with 60 percent of fresh fruits and vegetables and 80 percent of seafood coming from across our borders," it said.

The FDA can inspect just 1 percent of this food.

"Second, we are increasingly eating foods that are consumed raw and that have often been associated with foodborne illness outbreaks, including leafy greens such as spinach."

The FDA regulates 80 percent of the food supply, except for meat and processed egg products, which the U.S. Department of Agriculture regulates.

MORE AUTHORITY

The FDA has met some recommendations, GAO said. "For example, FDA reported in May 2008 that it created the Office of Chief Scientist," it said.

And it is working on a computer system that will predict which food imports are most likely to be contaminated. But GAO said Customs and Border Patrol was not alerting FDA when imports of food arrive.

The FDA should ask for more authority to regulate nutritional supplements, as well, the GAO said. The Dietary Supplement and Health Education Act, or DSHEA, covers most supplements and does not allow the FDA much intervention.

An Institute of Medicine report this month said the FDA needs new standards to measure the benefits of food, drugs and supplements. Committee members noted that consumers often wrongly assume the FDA regulates food and supplements in the same way it does drugs.

The GAO also said the FDA does not have the enforcement tools it needs.

"FDA does not have empirical research on consumer perceptions to support enforcement against misleading food labels," the report reads.

"For example, stakeholders from health, medical, and consumer organizations reported that 'whole grain' labels can be misleading because the product may contain little whole grain, 'transfat free' products may still be high in saturated fat, and 'natural' products may be highly processed."

Separately on Monday, the FDA and National Institutes of Health launched a new website to help report pre- and post-market safety data on food and drugs at www.safetyreporting.hhs.gov.

"We will now be able to analyze human and animal safety-related events more quickly and identify those measures needed to protect the public," FDA Commissioner Dr. Margaret Hamburg said in a statement.